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Ammonium chloride (NH4Cl) has been extensively studied as a transparent analogue for investigating the solidification of metals due to its distinctive properties and the simplicity of the experimentation. Furthermore, NH4Cl exhibits a striking resemblance in solidification behavior to the majority of binary eutectic alloy systems, rendering it a valuable model for studying phase transition phenomena. Experiments conducted on ammonium chloride are frequently employed to validate numerical models for predicting grain structures, macrosegregation, and the columnar-to-equiaxed transition (CET). This latter phenomenon arises due to differences in the velocities of columnar dendrite tips and the liquidus isosurface. However, the kinetics of dendrite tip growth, as a function of supersaturation, remains poorly understood for this commonly used alloy. The objective of this study was to utilize the available experimental data in conjunction with Ivantsov correlations to shed light on the ambiguous kinetics. The results indicate that when considering the crystal-melt density ratio, the Ivantsov solution offers a good correlation. Furthermore, incorporating a moderate interfacial kinetic coefficient enhances the correlations further. This correlation can be implemented in numerical models, which will aid in the determination of the columnar front, the columnar-to-equiaxed transition, and the equiaxed growth velocities.
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Due to the high computational costs of the Eulerian multiphase model, which solves the conservation equations for each considered phase, a two-phase mixture model is proposed to reduce these costs in the current study. Only one single equation for each the momentum and enthalpy equations has to be solved for the mixture phase. The Navier-Stokes and energy equations were solved using the 3D finite volume method. The model was used to simulate the liquid-solid phase transformation of a Fe-0.82wt%C steel alloy under the effect of both thermocapillary and buoyancy convections. The alloy was cooled in a rectangular ingot (100 × 100 × 10 mm3) from the bottom cold surface to the top hot free surface by applying a heat transfer coefficient of h = 600 W/m2/K, which allows for heat exchange with the outer medium. The purpose of this work is to study the effect of the surface tension on the flow and segregation patterns. The results before solidification show that Marangoni flow was formed at the free surface of the molten alloy, extending into the liquid depth and creating polygonized hexagonal patterns. The size and the number of these hexagons were found to be dependent on the Marangoni number, where the number of convective cells increases with the increase in the Marangoni number. During solidification, the solid front grew in a concave morphology, as the centers of the cells were hotter; a macro-segregation pattern with hexagonal cells was formed, which was analogous to the hexagonal flow cells generated by the Marangoni effect. After full solidification, the segregation was found to be in perfect hexagonal shapes with a strong compositional variation at the free surface. This study illuminates the crucial role of surface-tension-driven Marangoni flow in producing hexagonal patterns before and during the solidification process and provides valuable insights into the complex interplay between the Marangoni flow, buoyancy convection, and solidification phenomena.
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Secondary dendrite arm spacing (SDAS) is one of the most important factors affecting macrosegregation and mechanical properties in solidification processes. Predicting SDAS is one of the major parameters in foundry technology. In order to predict the evolution of microstructures during the solidification process, we proposed a simple model which predicted the secondary dendrite arm spacing based solely on the tip velocity (related to the tip supersaturation) and cooling rate. The model consisted of a growing cylinder inside a liquid cylindrical envelope. Two important hypotheses were made: (1) Initially the cylinder radius was assumed to equal the dendrite tip radius and (2) the cylindrical envelope had a fixed radius in the order of the dendrite tip diffusion length. The numerical model was tested against experiments using various Pb-Sn alloys for a fixed temperature gradient. The results were found to be in excellent agreement with experimental measurements in terms of SDAS and dendrite tip velocity prediction. This simple model is naturally destined to be implemented as a sub-grid model in volume-averaging models to predict the local microstructure, which in turn directly controls the mushy zone permeability and macrosegregation phenomena.
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Research efforts have been dedicated to predicting microstructural evolution during solidification processes. The main secondary arm spacing controls the mushy zone's permeability. The aim of the current work was to build a simple sub-grid model that describes the growth and coarsening of secondary side dendrite arms. The idea was to reduce the complexity of the curvature distribution with only two adjacent side arms in concurrence. The model was built and applied to the directional solidification of Al-06wt%Cu alloy in a Bridgman experiment. The model showed its effectiveness in predicting coarsening phenomena during the solidification of Al-06wt%Cu alloy. The results showed a rapid growth of both arms at an earlier stage of solidification, followed by the remelting of the smaller arm. In addition, the results are in good agreement with an available time-dependent expression which covers the growth and coarsening. Such model can be implemented as a sub-grid model in volume average models for the prediction of the evolution of the main secondary arms spacing during macroscopic solidification processes.
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OBJECTIVES: Sleep deprivation (SD) has been found to be associated with an increased incidence of adverse cardiovascular disease (CVD) events. The aim of this study was to investigate whether or not acute SD has a pathological effect on the geometry and the systolic and diastolic functions of the right and left heart chambers by standard transthoracic echocardiography (TTE) and speckle tracking echocardiography (STE) in healthy individuals with acute SD. METHODS: Nurses with no history of acute or chronic diseases underwent TTE and STE after working a night shift, a sleepless period of 24 h and 7 days of normal sleep after the night shift. Measurements of TTE and STE taken in the rested state were compared with those taken after 24 h of sleep deprivation. RESULTS: The study included 52 nurses (38 women, 73%). The mean age of the study population was 27.9 ± 7.4 years and mean BMI was 24.1 ± 4.8. Left atrial reservoir (51.5 ± 13.5 vs. 45.4 ± 10; p = 0.004), conduit (- 37.3 ± 11.3 vs. - 33.6 ± 7.9; p = 0.01), left ventricular global longitudinal strain (LVGLS, - 22.6 ± 2.4 vs. - 21.3 ± 2.4; p = 0.001), right ventricular global longitudinal strain (RVGLS, - 25.3 ± 3.7 vs. - 23.5 ± 3.9; p = 0.005) and right ventricular free wall longitudinal strain (RVFWSL, - 29.1 ± 4.2 vs. - 27 ± 4.5; p = 0.001) were impaired significantly after SD. CONCLUSION: This study is the first to investigate the negative effects of acute sleep deprivation on LV and RV strain in healthy adults using echocardiography. The findings showed that acute sleep deprivation leads to deterioration in function of both ventricles and left atrium. Speckle tracking echocardiography demonstrated subclinical diminished heart function.
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Privação do Sono , Disfunção Ventricular Esquerda , Adulto , Humanos , Feminino , Adulto Jovem , Privação do Sono/diagnóstico por imagem , Voluntários Saudáveis , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Átrios do Coração , Função Ventricular EsquerdaRESUMO
Introduction: The CHA2DS2-VASc (congestive heart failure, hypertension, age, diabetes mellitus, stroke, vascular disease and sex) score is a simple risk stratification algorithm to estimate stroke/thromboembolic risk in patients with non-valvular atrial fibrillation (AF). Higher pre-stroke CHA2DS2-VASc score is known to be associated with greater stroke severity and poorer outcomes. AF patients generally have higher CHA2DS2-VASc scores than non-AF patients. The Modified Thrombolysis in Cerebral Infarction (mTICI) score is the most widely used grading system to assess the result of recanalizing therapies in acute ischemic stroke (AIS). mTICI 2c and mTICI 3 are conventionally accepted as successful recanalization. Aim: We investigated whether pre-stroke CHA2DS2-VASc score is associated with mTICI recanalization score in AIS patients with and without AF undergoing percutaneous thrombectomy. Material and methods: One hundred fifty-nine patients with the diagnosis of AIS who were admitted within 6 h from symptom onset were included in the study (mean age: 65.7 ±12.9). All subjects underwent endovascular treatment. CHA2DS2-VASc scores of the participants were calculated. Subjects were grouped according to mTICI scores achieved after endovascular treatment. mTICI 2c and mTICI 3 were accepted as successful recanalization. Results: Successful reperfusion was observed in 130 (81.8%) of all patients who underwent endovascular treatment (mTICI flow ≥ 2c) and first-pass reperfusion was observed in 107 (67.3%) patients. When the patients with successful (mTICI flow ≥ 2c) and unsuccessful (mTICI flow ≤ 2b) reperfusion were divided into groups, no significant difference was observed between the patients in terms of comorbidities such as AF, hypertension, hyperlipidemia, coronary artery disease and cerebrovascular accident history. Patients with unsuccessful reperfusion were older than patients with successful reperfusion (71.4 ±11.2 vs. 64.5 ±13.01, p = 0.006), with a higher CHA2DS2-VASc score (4.1 ±1.5 vs. 3.04 ±1.6, p = 0.002). In addition, the duration of the procedure was longer in the unsuccessful reperfusion group (92.4 ±27.2 min vs. 65.0 ±25.1 min, p < 0.001). CHA2DS2-VASc score significantly correlated with successful recanalization (correlation coefficient; 0.243, p = 0.002). Multivariate logistic regression analysis revealed that only CHA2DS2-VASc score (OR = 1.43, 95% CI: 1.09-1.87, p = 0.006) and procedure time (OR = 1.03, 95% CI: 1.01-1.05, p < 0.001) were independent predictors of successful reperfusion. The receiver-operating characteristic (ROC) curve was used to determine the cut-off value for the CHA2DS2-VASc score that best predicts successful reperfusion. The optimal threshold was 3.5, with a sensitivity of 58.6% and specificity of 59.2% (area under the curve (AUC): 0.669, p = 0.005). Conclusions: For the first time in the literature, we investigated and demonstrated that pre-stroke CHA2DS2-VASc score was associated with success of recanalization as assessed with mTICI 2c and mTICI 3 in a cohort of AIS patients regardless of AF presence who underwent endovascular treatment. Our findings deserve to be tested with large scale long term studies.
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BACKGROUND: The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection had been investigated utilizing serology. MATERIALS AND METHODS: This community-based sero-survey was carried out in the neighborhoods of three cities in Saudi Arabia. RESULTS: Of 5629 participants, 2766 (49.1%) were women; and 2148 (38.1%) were 18-34 years of age, and 3645 (64.7%) were from South East Asia. Positive serology was seen in 2825 (50.2% (95% CI: 48.8-51.5%) for SARS-CoV-2 anti-S1 IgG antibodies by ECLIA. Being in the age category of 18-34 years and being from Eastern Mediterranean Region (country A) were associated with higher COVID-19 seropositivity with estimated odds ratio of 1.3 [95% CI 1.1-1.8] and 2.5 [95% CI 1.1.5-4.2] respectively. Gender, social status, education, nationality, symptoms, presence of comorbidities and activity style were positively associated with increased seropositivity. Factors associated negatively with the rate of seropositivity were higher education and having outdoor activity with estimated OR of 0.92 [95% CI 0.46-0.95] and 0.59 [95% CI 0.47-0.74], respectively. CONCLUSION: The study showed high seroprevalence of SARS-CoV-2 among high density population. Health education campaigns should target middle-aged, those with low education, those living in lower standards and indoor workers.
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COVID-19 , SARS-CoV-2 , Adolescente , Adulto , Anticorpos Antivirais , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Behçet's disease is a multisystem inflammatory disease that manifests with oral-genital ulcers, skin lesions, arthritis, and ophthalmologic and neurovascular findings. Neurological involvement of Behçet's disease is called neuro-Behçet's disease, and it is a difficult entity to diagnose because of insufficient symptoms. We present a 26-year-old male patient with complaints of headache, dizziness, and drop foot in the right lower extremity. He underwent gross total tumor resection with the preliminary diagnosis of low-grade glioma, according to the preoperative magnetic resonance imaging. Histopathological examination and further investigation revealed an interesting neuro-Behçet's disease case because of the localization and clinical occurrence of the lesion.
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Síndrome de Behçet , Glioma , Adulto , Síndrome de Behçet/complicações , Síndrome de Behçet/diagnóstico , Glioma/diagnóstico por imagem , Cefaleia , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
INTRODUCTION: Pituitary abscess is a rare lesion of the pituitary gland that can cause morbidity and mortality in the absence of appropriate treatment. They are classified as primary and secondary pituitary abscesses. Primary pituitary abscesses occur in patients with no previous pituitary pathology. Secondary pituitary abscesses are detected in patients with existing pituitary pathologies. CASE PRESENTATION: We report a 16-year-old female patient with primary pituitary abscess who was misdiagnosed initially and treated as meningitis. Following the visual disturbances, pituitary abscess was diagnosed, and she underwent abscess drainage via endoscopic endonasal transsphenoidal surgery and antibiotic treatment. CONCLUSION: Primary pituitary abscess can be clinically confused with other pathologies affecting the central nervous system. In order to avoid permanent sequelae in such patients, it should be kept in mind by physicians in similar cases. Satisfying results are obtained in these patients after appropriate treatment and dramatic improvement is achieved.
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Abscesso Encefálico , Meningite , Doenças da Hipófise , Neoplasias Hipofisárias , Adolescente , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/cirurgia , Criança , Endoscopia , Feminino , Humanos , Doenças da Hipófise/diagnóstico , Hipófise/diagnóstico por imagemRESUMO
Infective endocarditis (IE) is rarely seen in children, and it can cause significant morbidity and mortality. Congenital heart disease is a predisposing cardiac condition for IE and has an increasing prevalence. A mycotic aortic aneurysm is a rare disease due to infection and it has been reported that it may be a result of IE. We present a 10-year-old boy who was referred to our cardiovascular surgery department due to severe aortic stenosis (AS). Transthoracic echocardiography revealed calcific severe AS and computerized tomography (CT) angiography was performed to better evaluate the ascending aorta. CT angiography demonstrated a saccular aneurysm of the ascending aorta. The underlying pathology was considered as chronic IE on top of congenital AS with an unknown number of cusps. Histologic findings supported our diagnosis and accompanied by a saccular aneurysm. The patient underwent a successful aortic root enlargement, mechanical aortic valve replacement, and ascending aorta repair surgery.
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Aneurisma Infectado , Aneurisma Aórtico , Estenose da Valva Aórtica , Endocardite , Cardiopatias Congênitas , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/etiologia , Aneurisma Infectado/cirurgia , Aorta , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/cirurgia , Valva Aórtica , Criança , Endocardite/complicações , Endocardite/diagnóstico por imagem , Endocardite/cirurgia , Humanos , Masculino , TomografiaRESUMO
Pineal glioblastomas (GBMs) are extremely rare tumors. Herein we will present a pediatric patient with GBM located in pineal region who was admitted with the symptoms of increased intracranial pressure and treated with surgical resection and radiotherapy. Introduction: Pineal region tumors are extremely rare accounting for less than 1% of all brain tumors. The most common type of pineal region tumors is germ cell tumor, followed by pineal parenchymal tumors, gliomas, atypical tumors, and the others. Case Report: A 5-year-old girl was admitted with complaints of headache, dizziness, imbalance in walking, and impaired vision for 1 month. Her neurological examination revealed a tendency to sleep, anisocoric pupillae, mesh eye pupil, dilated lateral gaze paralysis, and left hemiparasia (4/5 muscle strength). In magnetic resonance imaging, a mass was observed in the pineal region that infiltrates the right thalamus and right superior peduncle, isointense and hyperintense in T1 sections, hyperintense in T2 sections, having centrally contrasted areas in post-contrast sections. Due to the presence of evident hydrocephalus, a ventricular shunt was inserted and then through supracerebellar to infratentorial approach the lesion was removed subtotally. The histopathological diagnosis was GBM. GBMs in the pineal region are extremely rare tumors carrying poor prognosis. The patients are generally presented with the signs and symptoms of increased intracranial pressure. GBMs should be kept in mind in differential diagnosis of tumors in the pineal region.
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INTRODUCTION: Thymic carcinoma metastases of the spinal column are very rare, especially in pediatric patients. To our knowledge, this is the first such pediatric case in the literature. CASE PRESENTATION: We report the case of a 14-year-old male patient with T12 and L1 metastases of thymic carcinoma. He had history of thymectomy and intrathoracic tumor resection 7 months previously. The patient's neurological condition deteriorated; therefore, tumor resection and decompression of the spinal canal were performed. He underwent instrumentation and fusion procedures to prevent spinal instability. CONCLUSION: The main purpose of the treatment is gross total resection of the thymic carcinoma. However, adjuvant methods such as radiotherapy and chemotherapy should be added to the treatment protocol in patients who have higher stage diseases or those in whom total tumor resection cannot be achieved.
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Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Timoma/cirurgia , Neoplasias do Timo/cirurgia , Adolescente , Humanos , Masculino , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Timoma/diagnóstico por imagem , Neoplasias do Timo/diagnóstico por imagemRESUMO
Type 2 diabetes mellitus (T2DM) is common in patients with heart failure (HF) and associated with considerable morbidity and mortality. Significant advances have recently occurred in the treatment of T2DM, with evidence of several new glucose-lowering medications showing either neutral or beneficial cardiovascular effects. However, some of these agents have safety characteristics with strong practical implications in HF [i.e. dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 receptor agonists (GLP-1 RA), and sodium-glucose co-transporter type 2 (SGLT-2) inhibitors]. Regarding safety of DPP-4 inhibitors, saxagliptin is not recommended in HF because of a greater risk of HF hospitalisation. There is no compelling evidence of excess HF risk with the other DPP-4 inhibitors. GLP-1 RAs have an overall neutral effect on HF outcomes. However, a signal of harm suggested in two small trials of liraglutide in patients with reduced ejection fraction indicates that their role remains to be defined in established HF. SGLT-2 inhibitors (empagliflozin, canagliflozin and dapagliflozin) have shown a consistent reduction in the risk of HF hospitalisation regardless of baseline cardiovascular risk or history of HF. Accordingly, SGLT-2 inhibitors could be recommended to prevent HF hospitalisation in patients with T2DM and established cardiovascular disease or with multiple risk factors. The recently completed trial with dapagliflozin has shown a significant reduction in cardiovascular mortality and HF events in patients with HF and reduced ejection fraction, with or without T2DM. Several ongoing trials will assess whether the results observed with dapagliflozin could be extended to other SGLT-2 inhibitors in the treatment of HF, with either preserved or reduced ejection fraction, regardless of the presence of T2DM. This position paper aims to summarise relevant clinical trial evidence concerning the role and safety of new glucose-lowering therapies in patients with HF.
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Cardiologia/normas , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Hipoglicemiantes/uso terapêutico , Compostos Benzidrílicos , Canagliflozina , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Europa (Continente) , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Glucose , Glucosídeos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Humanos , Liraglutida , Sociedades Médicas , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêuticoRESUMO
PURPOSE: Octogenarians with acute coronary syndromes have higher mortality and morbidity due to higher prevalence of comorbidities and frailty. The aim of this study was to explore the predictors of short and long term mortality in octogenarians with ACS. METHODS: Ninety-eight consecutive octogenarians presenting with acute coronary syndrome (mean age:84±3 years, 56 male) were included. All patients underwent coronary angiography and were given optimal medical treatment. The primary end point was cardiovascular mortality in hospital and at one year. RESULTS: Fifteen patients died during hospitalization and 20 patients died after discharge within the first year. ST-segment-elevation myocardial infarction and hypotension were significantly more prevalent in the in-hospital mortality group while atrial fibrillation and hyponatremia were more prevalent in the long-term mortality group. All deceased patients had significantly lower left ventricular ejection fraction and glomerular filtration rate. Cox analysis revealed ST-segment-elevation myocardial infarction, hypotension and left ventricular ejection fraction as independent predictors of in-hospital mortality while hyponatremia, atrial fibrillation and renal dysfunction as independent predictors of long term mortality. CONCLUSION: It would be reasonable to pay further attention to octogenarians with acute coronary syndrome if they are presenting with ST-segment-elevation myocardial infarction, and have hypotension, impaired left ventricular function, hyponatremia, atrial fibrillation or renal dysfunction, which are associated with increased mortality.
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Síndrome Coronariana Aguda/mortalidade , Idoso , Idoso de 80 Anos ou mais , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Infarto do Miocárdio/mortalidade , Intervenção Coronária Percutânea , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Fatores de TempoRESUMO
OBJECTIVE: The aim of this study was to assess the efficacy and feasibility of an enhanced heart failure (HF) education with a 6-month telephone follow- up program in post-discharge ambulatory HF patients. METHODS: The Hit-Point trial was a multicenter, randomized, controlled trial of enhanced HF education with a 6-month telephone follow-up program (EHFP) vs routine care (RC) in patients with HF and reduced ejection fraction. A total of 248 patients from 10 centers in various geographical areas were randomized: 125 to EHFP and 123 to RC. Education included information on adherence to treatment, symptom recognition, diet and fluid intake, weight monitoring, activity and exercise training. Patients were contacted by telephone after 1, 3, and 6 months. The primary study endpoint was cardiovascular death. RESULTS: Although all-cause mortality didn't differ between the EHFP and RC groups (p=NS), the percentage of cardiovascular deaths in the EHFP group was significantly lower than in the RC group at the 6-month follow up (5.6% vs. 8.9%, p=0.04). The median number of emergency room visits was one and the median number of all cause hospitalizations and heart failure hospitalizations were zero. Twenty-tree percent of the EHFP group and 35% of the RC group had more than a median number of emergency room visits (p=0.05). There was no significant difference regarding the median number of all-cause or heart failure hospitalizations. At baseline, 60% of patients in EHFP and 61% in RC were in NYHA Class III or IV, while at the 6-month follow up only 12% in EHFP and 32% in RC were in NYHA Class III or IV (p=0.001). CONCLUSION: These results demonstrate the potential clinical benefits of an enhanced HF education and follow up program led by a cardiologist in reducing cardiovascular deaths and number of emergency room visits with an improvement in functional capacity at 6 months in post-discharge ambulatory HF patients.
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Insuficiência Cardíaca/prevenção & controle , Alta do Paciente , Educação de Pacientes como Assunto , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , TurquiaRESUMO
OBJECTIVE: Although numerous studies have shown the protective effects of the well-developed coronary collaterals on left ventricular functions, the relationship between collateral grade and left ventricular end diastolic pressure has not been studied in chronic total occlusion patients. Also, there are conflicting data on the effect of collaterals on NT-proBNP levels. The aim of our study was to evaluate the relationship between coronary collateral circulation and left ventricular end diastolic pressure and NT-proBNP levels in chronic total occlusion patients. METHODS: Study group was retrospectively selected from the patients who had undergone coronary angiography at our hospital between June 2011 and March 2013. Clinical, biochemical, angiographic and hemodynamic data of 199 consecutive patients having at least one totally occluded major epicardial coronary artery were evaluated. Coronary collateral circulation was graded according to Rentrop classification. While Rentrop grade 3 was defined as well-developed, all the remaining collateral grades were regarded as poor collaterals. RESULTS: Overall 87 patients were found to have good collaterals and 112 patients had poor collaterals. There was no significant difference between the patients with well- or poorly developed coronary collaterals with regard to left ventricular end diastolic pressure (16.84 ± 5.40 mmHg vs 16.10 ± 6.09, respectively, p = 0,632) and log NT-proBNP (2.46 ± 0.58 vs 2.59 ± 0.76, respectively, p = 0,335). CONCLUSION: In patients with coronary chronic total occlusion even well-developed coronary collaterals are not capable of protecting the rise of left ventricular end diastolic pressure and NT-proBNP levels which are reliable markers of the left ventricular dysfunction.
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BACKGROUND: Preventing liver damage that might lead to cirrhosis is very important in the early stages of injury to that organ. The role of mast cells (MCs) in liver injuries has been long debated, and vitamin E is a well-known antioxidant used to treat those injuries. This study aimed to determine the protective role of vitamin E on MCs in injury to the liver that is triggered by carbon tetrachloride (CCl4). There is a correlation between MC deposits and improvement in fibrosis tissues. METHODS: To further examine this, 68 male Albino Wistar rats were divided randomly into five groups: the control group, the vitamin E group, the CCl4 group, the CCl4 + vitamin E group, and the vitamin E + CCl4 group. Malondialdehyde (MDA) analysis, MC counts, histopathological investigation, and statistical analyses were used to evaluate the findings. RESULTS: The administration of CCl4 resulted in an increase in the accumulation of MCs, degenerative parenchyma cells, MDA level, steatosis and inflammation. Additionally, proliferation of the bile ducts in the portal area and porto-portal and porto-central fibrosis were observed in the CCl4 group. In contrast, in the vitamin E group and in the groups administered a combination of vitamin E and CCl4, vitamin E prevented these increases. CONCLUSION: It was concluded that the significant decrease in the MC counts, in the level of MDA and the number of degenerative cells, as well as a decrease in the steatosis and inflammation scores showed that vitamin E could prevent liver injuries by protecting the organ's histological architecture. Finally, the results indicate that vitamin E has positive effects on liver injuries.
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Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Citoproteção/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Vitamina E/farmacologia , Doença Aguda , Animais , Antioxidantes/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/sangue , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
OBJECTIVE: Arterial stiffness parameters including pulse wave velocity (PWV) and augmentation index (AIx) are associated with increased risk of cardiovascular disease. A close relationship has been demonstrated between vitamin D deficiency and cardiovascular disease. The aim of the present study was to investigate effects of vitamin D deficiency and supplementation on arterial stiffness parameters in patients with normal cardiac functions. METHODS: Study population consisted of 45 patients with vitamin D deficiency and normal cardiac functions. Median age (interquartile range) was 45.0 (12.00) years, and 33 patients were female. Patients were treated with oral administration of vitamin D3. Arterial stiffness parameters were evaluated using Mobil-O-Graph arteriograph system, which detected signals from the brachial artery before and after treatment. RESULTS: Vitamin D levels significantly increased after treatment (9.0 [6.00] nmol/L vs 29.0 [11.50] nmol/L, p<0.001). No significant difference was observed among conventional echocardiographic parameters before or after treatment. Post-treatment PVW and AIx were significantly lower than baseline measurements (6.8 [1.55] m/s vs 6.4 [1.30] m/s, p<0.001 and 23.0 [22.00]% vs 31.0 [14.50]%, p<0.001, respectively). Baseline vitamin D levels significantly correlated with PWV (r=-0.352, p=0.018). Post-treatment vitamin D levels also significantly correlated with post-treatment PWV (r=-0.442, p=0.002) and AIx (r=-0.419, p=0.004). Multivariate linear regression analysis revealed no independent predictor of baseline log-transformed PWV. CONCLUSION: Vitamin D supplementation has beneficial effects on arterial stiffness. Arterial stiffness parameters may aid in the assessment of cardiovascular risk in patients with vitamin D deficiency.